The efficacy and safety of ketamine in the treatment of super-refractory status epilepticus: a systematic review

Ketamine, as an anesthetic, has been considered for terminating status epilepticus (SE); however, due to the urgency and severity of the condition, there are currently no randomized controlled trials internationally assessing the efficacy of ketamine for treating super-refractory status epilepticus. Similarly, there appears to be a lack of systematic reviews addressing this topic in the literature. Therefore, this systematic review aims to explore the effectiveness and safety of ketamine for terminating super-refractory status epilepticus. We conducted a systematic search on PubMed, EMBASE, and Web of Science databases. Manuscripts unrelated to the research on super-refractory status epilepticus were excluded, as were manuscripts published in non-English languages. The quality assessment and risk of bias were evaluated using the MINORS criteria. Data extraction was limited to qualitative synthesis due to the unsuitability of the data for meta-analysis. Out of 782 studies retrieved from electronic databases, 11 met the inclusion criteria. Among them, 10 studies were retrospective, and 1 study was prospective. Patient data for inclusion were sourced from the case registries of the researchers' respective hospitals. Across all included studies, the administration of ketamine significantly reduced the duration of status epilepticus and demonstrated higher safety compared to patients not receiving ketamine treatment for super-refractory status epilepticus. Additionally, early administration of ketamine correlated with improved treatment outcomes. The risk of bias across all studies was deemed low. This systematic review suggests that ketamine may be a feasible treatment option for super-refractory status epilepticus. However, given the critical nature of super-refractory status epilepticus, clinicians should prioritize its termination over evaluating the efficacy of specific medications, ensuring patient safety remains paramount. If feasible in real-world medical settings, future research should focus on designing randomized controlled trials to observe the specific efficacy and mechanisms of ketamine. Careful validation is necessary before considering ketamine as a first-line treatment for super-refractory status epilepticus.